Thermodynamic modeling of the Mg-Ge-Si, Mg-Ge-Sn, Mg-Pb-Si and Mg-Pb-Sn systems

The complete literature review and critical thermodynamic optimization of the Mg-Ge-Si, Mg-Ge-Sn, Mg-Pb-Si and Mg-Pb-Sn systems have been performed in the present study. The thermodynamic behavior of liquid solution was described by the Modified Quasichemical Model, which takes into account the short-range-ordering tendency of first-nearest-neighbor atoms. The Mg2X solid solution (X = Ge, Pb, Si, Sn) was modeled with the assumption of random mixing of X atoms in the solution. As results of the present thermodynamic modeling, the experimentally unexplored ternary phase diagrams of the Mg-Ge-Si, Mg-Ge-Sn and Mg-Pb-Si systems were predicted for the first time. The variation of mixing enthalpy of liquid phase can be accurately explained by the Modified Quasichemical Model.